Footwear with adjustable-length shank

ABSTRACT

To provide a roller skate of adjustable length, a first shank member and a second shank member overlap and are held at any one of several positions by a leaf spring that has its base mounted to the top shank member and has a tab on its other end receivable between any of several parallel arms with a slot of the bottom shank member. It is held to the top member by a bolt having its head rigidly affixed to the top member and its threaded portion in the slot in the bottom member which bottom member is between the top member and the spring. To change the length of the roller skate, a finger grip on the end of the leaf spring is pulled downward to remove the tab from between two pairs of arms and the members are adjusted in length, after which, the tab is inserted between two other pairs of arms.

Jan. 18, 1972 w. G. MARTIN FOOTWEAR WITH ADJUSTABLE-LENGTH SHANK Filed Aug. 8, 1969 weae gzzzmt yz United States Patent O 3,635,854 FOOTWEAR WITH ADJUSTABLE-LENGTH SHANK Wesley G. Martin, Mauitowoc, Wis., assignor to Aluminum Specialty Company, Manitowoc, Wis. Filed Aug. 8, 1969, Ser. No. 848,626 Int. Cl. A63c 17/02 US. Cl. 280-1116 7 Claims ABSTRACT OF THE DISCLOSURE To provide a roller skate of adjustable length, a first shank member and a second shank member overlap and are held at any one of several positions by a leaf spring that has its base mounted to the top shank member and has a tab on its other end receivable between any of several parallel arms within a slot of the bottom shank member. It is held to the top member by a bolt having its head rigidly affixed to the top member and its threaded portion in the slot in the bottom member which bottom member is between the top member and the spring. To change the length of the roller skate, a finger grip on the end of the leaf spring is pulled downward to remove the tab from between two pairs of arms and the members are adjusted in length, after which, the tab is inserted between two other pairs of arms.

This invention relates to footwear and more particularly relates to adjustable-length footwear such as adjustable-length roller skates.

Generally, each item of adjustable-length footwear includes an adjustable-length shank between the toe platform and heel platform. To render the shank adjustable in length, a first shank member is fastened to the heel platform and a second shank member is fastened to the toe platform, with the first and second members overlapping. each other across adjustable amounts of their lengths and being held together with the selected amount of overlapping by a latch.

In the prior art shanks, the first and second shank members are telescoping parts, the inner part being a sturdy beam attached to the heel platform and the outer part being a regular tube attached to the toe platform. The inner portion of the shank includes the latch, which is a spring mounted plunger that is pulled into a slot by the spring to lock the two telescoping parts of the shank against movement. With this mechanization, the shank of the footwear is adjusted in length by pulling the springbiased plunger out of the slot and sliding the two parts of the shank further apart or closer together and then returning the plunger into another slot at a different location to lock the two parts of the shank against further longitudinal movement.

The prior art adjustable-length footwear has several disadvantages, which are: (1) they have an excessive number of parts; (2) they are expensive to fabricate; and (3) they are excessively complex in construction. These disadvantages result from the use of the plunger as a latch. The plunger requires a guide and a biasing helical spring. Moreover, additional supports such as telescoping parts are necessary to hold the toe platform and the heel platform against bending motion with respect to each other because the plunger only holds them against lateral motion in the direction that the two members of the shank telescope together.

Accordingly, it is an object of the invention to provide novel adjustable-length footwear.

It is a further object of the invention to provide adjustable-length footwear that is simple in construction and inexpensive.

It is a further object of the invention to provide adjust- Patented Jan. 18, 1972 able-length footwear each item of which is easy to assemble and has few parts.

It is a still further object of the invention to provide adjustable-length footwear in which a latch holds the two members of the shank of each item of footwear against both longitudinal movement and bending movement with respect to each other.

It is a still further object of this invention to provide a novel latch for adjustable-length footwear.

In accordance with the above and further objects of the invention, adjustable-length footwear is provided, each item of which has a toe platform, a heel platform, and a shank between the toe platform and heel platform, with the shank being adjustable in length. The shank includes a first member formed integrally with the toe platform, a second member formed integrally with the heel platform and a latch for holding the first member and the second member together with a selected amount of overlapping between them.

The latch includes a longitudinal slot in one of said first and second members, which slot has a plurality of arms extending into it from its sides, in pairs, with each pair being parallel to the other pairs and with each arm in a pair extending toward the other arm of the pair from the opposite side of the slot a sufficient distance to leave only enough space between their ends to permit a fastener to slide past them. One end of a leaf spring abuts the one member on its side opposite to the other member and is fastened to the other member. A shank portion of the fastener extends through the slot in the one member so that the one member is sandwiched between the other member and the end of the leaf spring.

With this arrangement, the leaf spring holds the two members together in overlapping relationship and the two members can move longitudinally with respect to each other with the shank portion of the fastener moving along the slot as the total length of the shank of the item of footwear is adjusted. The other end of the leaf spring includes a tab extending upwardly from one face and a finger grip extending downwardly from the opposite face, with the tab being of such a size that it fits into the slot between any two of the parallel pairs of arms to lock the two members in longitudinal position. The tab may be pulled out of the slot by means of the finger grip to adjust the length of the adjustable-length shank of the item of footwear. The adjustable-length shank for the footwear is inexpensive because it consists of only a few parts of simple construction that are assembled together easily. The latch not only provides a length adjustment to render the footwear adjustable in length, but also aids in supporting the two main portions of the shank. Because of this combined function, the latch simplifies the structure required to provide an adjustable length shank for the footwear.

The invention and the above noted and other features thereof will be better understood from the following detailed description when considered with references to the accompanying drawings in which:

FIG. 1 is a perspective view of a roller skate including an embodiment of the invention;

FIG. 2 is a perspective, fragmentary, exploded view of an adjustable-length shank for the roller skate shown in FIG. 1;

FIG. 3 is a fragmentary bottom view of the adjustablelength shank for a roller skate;

FIG. 4 is a rear elevational view of the roller skate; and

FIG. 5 is a sectional view taken through lines 5-5 of the roller skate.

GENERAL CONSTRUCTION OF THE SKATE In FIG. 1, a perspective view of a roller skate 10 for which the adjustable-length footwear is especially suited is shown having a toe portion 12, a shank 14, and a heel portion 16.

The toe portion 12 of the roller skate includes a toe platform 18, a toe clamp or stirrup 20, and a front roller wheel assembly 22. The toe platform 18 is formed of flat sheet metal such as steel or aluminum shaped to accommodate the toe portion of a shoe and has a downturned flange 24 extending around its edge. The toe clamp 20 includes an arcuate top portion adapted to fit over the toe of a shoe and inwardly extending side portions passing through openings in the fiange 24 and being spot welded to the bottom of the platform 18. The roller wheel assembly 22 includes an axle 26 extending parallel to the platform 18 and receiving the inner racer of ball bearing assemblies such as 28, which ball bearing assemblies support the front roller wheels 30 and 32 on the outer ball bearing racer of the ball bearing assemblies 28 in a rotatable arrangement with axle 26. The axle 26 is mounted by a yoke 34 to the bottom of the toe platform 18.

The heel portion 16 of the roller skate 10 includes a heel platform 36, a heel clamp 38, heel straps 40, and a rear roller wheel assembly 42.

The heel platform 36 is of sheet metal such as steel or aluminum shaped to conform to the heel of a shoe. It has a downturned flange 44 around its edge and in its bottom surface has two parallel channels 46 and 48 formed as half-cylinders extending upwardly from the top surface of the platform.

The heel support clamp 38 is a rearwardly extending arcuate metal section such as steel or aluminum formed integrally with the platform 36 and includes slots to accommodate the straps 40. The straps 40 are adapted to fit around the ankle of the wearer and be buckled together by a buckle 50.

The rear roller wheel assembly 42 includes an axle mounted to the rear of the heel platform 36 by a metal yoke such as steel or aluminum. The inner racer of each of two ball bearing assembly is held by a hub cap such is 52 to a different end of the axle. The two roller wheels 54 and 56 are rotatably supported on the outer racer of the ball bearing assemblies.

The shank portion 14 of the roller skate 10 includes a first member 58 formed integrally with the toe platform 18 and a second member 60 formed integrally with the heel platform 16. The first member 58 and the second member 60 of the shank 14 both include downwardly extending flanges from their side edges. A portion of the first member 58 fits within the second member 60 and the first and second members are held together by a latch.

The latch includes a fastener such as the bolt 62 which passes through both members from the top of the shank 14 to the bottom of the shank. To permit the two members 58 and 60 of the shank to be moved with respect to each other for the purpose of increasing or decreasing the amount of overlapping between them, a central longitudinally extending slot 64 is provided in the member 58 to receive the threaded portion of the bolt 62 and to permit the bolt to move along the member 58 within the slot 64.

ADJUSTABLE-LENGTH SHANK In FIG. 2 a fragmentary, exploded, perspective view of the adjustable-length shank 14 is shown including the bolt 62, the first member 58, the second member 60, and a compression washer or leaf spring 66. The bolt 62, the leaf spring 66, and the slot 64 in the first member 58 from a latch for the adjustable-length shank 14. The first member 58 of the shank is sandwiched between the second member 60 and the leaf spring 66 and held therebetween by the bolt 62 and its nut 68. The leaf spring 66 exerts pressure between the first and second members to hold them rigidly one against the other, but permits the two to slide with respect to each other unless the latch is closed.

To hold the first member 58 and the second member 60 together in such a manner that they can not bend with respect to each other and yet can 'move longitudinally, the bolt 62 includes a head 70, a square shank portion 72 adjacent to the head, and a threaded end 74 adapted to receive the threaded nut 68. The second member 60 includes a centrally located square aperture 76 large enough to receive the square shank 72 of the bolt 62 but not large enough to permit the head of the bolt 62 to pass therethrough. The slot 64 in the first member 58 is of such a width as to loosely receive the square shank 72 so that, in adjusting the length of the adjustable-length shank 14, the square shank 72 slides along the slot 64 of the first member 58 while being held rigidly in the second member 60.

To latch the first member 58 and the second member 60 in place, the leaf spring 66 includes an upwardly extending tab 78 and a downwardly extending finger grip 80. The first member 58 includes a plurality of cross slots 82 extending transverse to the longitudinal slot 64 to form a plurality of arms extending into the slot 64 from its sides, pairs, with each pair being parallel to the other pairs and with each arm in a pair extending toward the other arm of the pair from the opposite sides of the slot a sufficient distance to leave only enough space between their ends to permit a fastener to slide past them. The cross slots 82 are of sufiicient size to receive the tab 78.

As best shown in FIG. 3, the tab 78 is pulled into a selected one of the cross slots 82, and when in this selected cross slot, prevents the first member 58 from moving with respect to the second member 60 in a longitudinal direction. To prevent the first member 58 from moving with respect to the second member 60, a connection is formed between these parts, through the following elements: the first member 58, the tab 78 of the leaf spring 66, the square shank 72 of the bolt 62, the square shank 72 of the bolt 62 and the second member 60 in the order named.

To release the latch, the finger grip 80 is pulled downwardly (the upward direction shown in the bottom view of FIG. 3) removing the tab 78 from the slot 64 so that the square shank 72 of the bolt 62 slides within the slot 64 to adjust the length of the adjustable-length shank 14. The shank 14 is adjusted to any of the discrete positions pegmitted by the alignment of a cross slot 82 with the ta 78.

To prevent the toe and heel platforms from bending in the same plane with respect to each other about the fastener, the first member 58 includes two parallel arcuate upwardly extending channels 84 and 86 forming halfcylinders adapted to fit within the channels 46 and 48 of the second member 60 as best shown in FIGS. 2 and 5. The two upwardly extending channels 84 and 86 are held within the channels 46 and 48 respectively by the leaf spring 66 and bolt 62 which compress the first and second members together.

To prevent the toe and heel platform from bending in a direction transverse to their plane with respect to each other about the fastener, the end of the first member 58 extends rearwardly a considerable distance as best shown in FIG. 4. A yoke 88, which supports the rear axle 90, includes a yoke body having two parallel arms 92 and 94 extending upwardly from each of its sides with outwardly turned flanges 96 and 98 spot welded to the bottom or the heel platform 36 to support the yoke. The distal end of the first member 58 is received between the inner top portion of the yoke 88 and inwardly extending ears (not shown) on the yoke body 88. With this construction, the end of the first member 58 is limited in its upward and downward motion by the bottom of the heel platform 36 and the top of the yoke 88 or ears upon the yoke 88.

OPERATION To adjust the length of an item of footwear so that it tits a shoe, the latch on the adjustable-length shank 14 of the footwear is released. The movable members 58 and 60 of the shank are moved with respect to each other to lengthen or shorten the shank and the movable members are again latched in place.

To release or unlatch the movable members, the footwear such as the roller skate is turned so that its bottom is upward. The finger grip 80 of the leaf springs 66 is then grasped and pulled upwardly or away from the toe and heel platforms 18 and 36 until the tab 78 has been extracted from its cross slot 82. With the tab 78 extracted from its slot 82, the toe portion 12 and the heel portion 16 are moved with respect to each other to cause the first member 58 and the second member 60 of the adjustablelength shank to slide. As the first member 58 and the second member 60 of the adjustable-length shank 14 slide with respect to each other, the square shank 72 of the bolt 62 slides within the slot 64 of the first member 58 while the bolt 62 is held firmly to the second member 60 of the shank by the square aperture 76 and the square shank 72 of the bolt 62. The first and second members 58 and 60 are free to slide with respect to each other as long as the tab 78 is not in one of the cross slots 82 and they can be latched only at certain locations.

To relatch the first member 58 to the second member 60 at a desired length of the shank 14, the tab 78 of the leaf spring 66 is permitted to drop into the closest one of the cross slots 82. The tab 78 is held within this slot by the leaf spring 66 which is pulled against the first member 58 by the threaded nut 68 of the bolt 62.

Once the two members are latched, they are not free to bend sideways or upwardly. The leaf spring 66 holds them firmly together. Moreover, sideways bending between the first member 58 and the second member 60 is impeded by the interfitting channels 46 and 48 on the second member 60 with the channels 84 and 86 on the first member 58. Bending movement upward and downward is prevented by overlapping of the members and the pressure exerted against the two by the spring 66. Additional positive stops against bending in this direction are provided by the opening formed with the rear yoke 88 of the heel portion which opening receives the end of the first member 58. Within this opening the downwardly extending flanges 24 of the first member 58 are limited in downward motion with respect to the heel platform 36 by the top surface of the yoke and by ears (not shown) formed on the upwardly extending arms 92 and 94 of the yoke and the top of the first member 58 is limited in upward motion by the bottom of the heel platform 36.

From the above description it can be understood that the adjustable-length footwear 10 of this invention, has few parts each of which are inexpensively formed so that each item of the adjustable-length footwear is economical. Moreover, it is easy to adjust because of the simplicity of the arrangement.

Although a specific embodiment of the invention has been described in some detail, many modifications and variations in the invention are possible in the light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. An adjustable-length section for footwear having a toe platform and a heel platform, comprising:

a first member integrally formed with the toe platform,

a second member integrally formed with the heel platform,

said first and second members being overlapping members, and

biasing means for biasing said first and second members against each other in their overlapping portions and for locking said members against motion with respect to each other in a direction transverse to the biasing direction,

said biasing means including a locking means having first and second engaging parts,

said second engaging part being a slotted openingin one of said first and second members-provided with cross slots and said first engaging part being a protrusion shaped to fit into said opening in detentive engagement with said cross slots,

said biasing means further including a resilient means mounted beneath said overlapping first and second members and adapted to exert a compressive force thereon,

said resilient means having a base mounted to the other of said first and second members and having a movable end with a finger grip extending downwardly therefrom,

said first engaging means being mounted to said movable end of said resilient means and extending upwardly therefrom and said second engaging means being immovably fixed with respect to the other of said first and second members.

2. An aljustable-length section for footwear according to claim 1 in which said opening is integrally formed in said first member.

3. An adjustable-length section for footwear according to claim 1 in which said biasing means further includes:

a fastener passing through the overlapping portions of said first and second members and through the base of said resilient means to hold said first and second members and said resilient means together at one point;

said fastener being movable with respect to one of said first and second members and being fixed in position with respect to the other of said first and second members and with respect to said resilient means.

4. An adjustable-length section for footwear according to claim 2 in which said first member includes said slotted opening and said fastener includes a portion movable within slotted opening.

5. An adjustable-length section for footwear according to claim 1 in which said first and second members have aligned guides formed complementarily with each other to prevent said first and second members from lateral movement with respect to each other.

6. A roller skate including the item of adjustable-length footwear of claim 1 and further comprising:

a first pair of roller wheels attached to said toe platform;

a second pair of roller wheels attached to said heel platform;

a toe clamp fastened to said toe platform; and

a heel support fastened to said heel platform.

7. A roller skate according to claim 6 in which said cross slots of said biasing means are formed by arms extending from a longitudinal slot within said first member.

References Cited UNITED STATES PATENTS 967,742 8/1910 Eckart 280-l 1.26 1,910,193 5/1933 Ware 280ll.26 3,291,498 12/ 1966 Frisbie ct al 280-l 1.26

BENJAMIN HERSH, Primary Examiner M. L. SMITH, Assistant Examiner 

